It's nice to have an extra display so I can use it to show additional things like the weather, schedule, and calendar. I also use it to watch movies while I work. Surprisingly, it also has built-in speakers.
HP 24Uh 24" Backlit Monitor 1920x1080p, 60Hz, LCD with HD Resolution - K5A38AA#ABA
101 Review
Samsung Flat Monitor Super Slim Design 27", 1920X1080P, 75Hz, Flicker Free
112 Review
Dell E2318Hx LED Lit Monitor: High-Definition Display with Flicker-Free Technology and IPS Panel
109 Review
Dell SE2416HX Screen LED Lit Monitor 23.8", 1920X1080P, HDMI
93 Review